Typically, for a plumbing fixture (e.g., a faucet, a tub spout, a shower head), a valve body conveys water flowing from a main water source to a desired destination (a sink, a tub, a basin). The valve body generally has two water inlet passages through which cold water and hot water from the main water source can respectively flow. The valve body also has a water outlet passage through which the cold water, the hot water or a mixture of the cold and hot water can be discharged to an outlet portion of the plumbing fixture (e.g., a spout). In a one-handle version of the valve body, the valve body has a cavity for receiving a valve cartridge which allows a user to control the flow rate and the temperature of the water flowing through the water inlet passages to the water outlet passage using a single valve actuating mechanism.
One type of valve cartridge is a structural assembly including a housing in which two or more disks, plates or the like are disposed. The disks are generally made of a hard material (e.g., ceramic or metal). At least one of the disks (i.e., a fixed disk) is fixed with respect to the housing. Another of the disks (i.e., a movable disk) is disposed above the fixed disk and is movable with respect to the fixed disk. The valve cartridge includes the actuating mechanism that is directly or indirectly connected at one end to the movable disk. Another end of the actuating mechanism extends through an opening in the housing for manipulation by a user. The end of the actuating mechanism extending through the opening in the housing can be connected to a handle, knob or the like to assist the user in operating the valve cartridge.
In a one-handle version of this type of valve cartridge for use in the one-handle version of the valve body, the fixed disk includes two inlet openings (i.e., a cold water inlet opening and a hot water inlet opening) that substantially align with the water inlet passages of the valve body when the valve cartridge is installed in the valve body. Furthermore, the fixed disk includes an outlet opening that substantially aligns with the water outlet passage of the valve body when the valve cartridge is installed in the valve body. The actuating mechanism is connected to the movable disk via a coupling. The actuating mechanism can be pivoted to cause translational movement of the movable disk. The actuating mechanism can be rotated to cause angular movement of the movable disk.
In this manner, the movable disk can assume different positions with respect to the fixed disk. In particular, pivoting of the actuating mechanism changes the flow rate of the water from zero to a maximum flow rate, whereas rotation of the coupling changes the temperature of the water. Accordingly, a one-handle actuating mechanism can control both the flow rate and the temperature of the water flowing through the valve cartridge.
The valve cartridge also includes one or more seals for preventing water from leaking out of the valve cartridge. The seals can be located, for example, below, between and/or above the disks in the valve cartridge. When the valve cartridge is installed in the valve body, a retention nut is used to secure the valve cartridge in the valve body. The retention nut engages the housing of the valve cartridge such that the seals in the valve cartridge are compressed and, thus, apply a loading force to the components (including the disks) in the valve cartridge. Accordingly the fixed disk and the movable disk are kept in water tight contact after installation of the valve cartridge in the valve body.
As one example, a conventional valve cartridge 100 is illustrated in FIGS. 1A-1C and also illustrated in U.S. Pat. No. 7,063,106. As shown in FIGS. 1A-1B, the conventional valve cartridge 100 has several discrete components including a housing 102, a lower seal 104, a bottom member 106, an upper seal 108, a fixed plate 110, a mobile plate 112, a carrier 114, a rotatable support member 116, an operating lever 118 and a cover 120. The housing 102 has a tubular shape for receiving the components of the valve cartridge 100.
The operating lever 118 is part of the actuating mechanism of the valve cartridge 100. The operating lever 118 is connected to the rotatable support member 116 via a pin 122. A lower surface of the rotatable support member 116 rests on an upper surface of the carrier 114. The rotatable support member 116 can rotate relative to the housing 102. A portion of the operating lever 118 extends below the rotatable support member 116 and into the housing 102 which facilitates connecting the operating lever 118 to the mobile plate 112 via the carrier 114, as described below. A portion of the operating lever 118 extends above the rotatable support member 116 and out of the housing 102 which facilitates connecting the operating lever 118 to an operating member (not shown), such as a handle, a knob or the like.
The housing 102 has an internal shoulder 124 formed near a lower opening of the housing 102, wherein the internal shoulder 124 is shaped to receive a correspondingly shaped portion of the bottom member 106. The cover 120 has teeth 126 that snap fit into openings 128 formed near an upper opening of the housing 102. Accordingly, the lower opening of the housing 102 is closed by the bottom member 106 and the upper opening of the housing 102 is closed by the cover 120, thereby securing the components in the valve cartridge 100.
The fixed plate 110 has a pair of water inlet passages 130 (only one of which is visible in FIGS. 1A-1C) and a water outlet passage 132. The fixed plate 110 is disposed above the bottom member 106. The mobile plate 112 is supported on top of the fixed plate 110 and can slide on top of the fixed plate 110. The mobile plate 112 includes a mixing chamber 134 for mixing cold and hot water flowing into the valve cartridge 100 through the respective water inlet passages 130 in the fixed plate 110. The mixed water then flows out of the valve cartridge 100 through the water outlet passage 132 in the fixed plate 110.
The carrier 114 and the rotatable support member 116 function to translate movement of the operating lever 118 into movement of the mobile plate 112. A lower portion of the carrier 114 engages an upper portion of the mobile plate 112. An upper portion of the carrier 114 has a recess 136 for receiving a lower end 138 of the operating lever 118, thereby connecting the operating lever 118 (which is connected to the rotatable support member 116 via the pin 122) to the carrier 114 and the mobile plate 112.
The lower seal 104 fits in a recess on a lower surface of the bottom member 106 and the upper seal 108 fits in a recess on an upper surface of the bottom member 106. The lower seal 104 forms a water tight seal between a valve body 140 in which the valve cartridge 100 is installed and the bottom member 106 (see FIG. 1C). The upper seal 108 forms a water tight seal between the bottom member 106 and the fixed plate 110 (see FIG. 1B). The lower seal 104 and the upper seal 108 prevent water from leaking out of the valve cartridge 100.
As shown in FIG. 1C, when the valve cartridge 100 is installed in the valve body 140 of the plumbing fixture 142 (e.g., a faucet), a retention nut 144 is used to secure the valve cartridge 100 in the valve body 140. The retention nut 144 engages the housing 102 of the valve cartridge 100 such that the seals 104 and 108 in the valve cartridge 100 are compressed and, thus, apply a loading force to the components (including the fixed plate 110 and the mobile plate 112) in the valve cartridge 100. Accordingly the fixed plate 110 and the mobile plate 112 are kept in water tight contact after installation of the valve cartridge 100 in the valve body 140.
The position and the orientation of the mobile plate 112 relative to the fixed plate 110 are controlled by the operating lever 118 projecting out of the housing 102. In particular, the operating lever 118 can be pivoted within the rotatable support member 116 about the pin 122 and can cause the rotatable support member 116 to rotate with the operating lever 118. The operating member (not shown) can be connected to the operating lever 118 to facilitate manipulation of the operating lever 118 by the user. Accordingly, after the valve cartridge 100 is installed in the valve body 140, the user can manipulate the operating member which moves the operating lever 118 to change the position and/or orientation of the mobile plate 112 relative to the fixed plate 110, thereby controlling the flow rate and/or the temperature of the water flowing through the valve cartridge 100 and out the plumbing fixture 142, such as through a spout 146 (see FIG. 1C).
Because the components in the valve cartridge 100 (e.g., the bottom member 106, the fixed plate 110, the mobile plate 112, the carrier 114 and the rotatable support member 116) are stacked on top of one another, the compression of the lower seal 104 and the upper seal 108 forces the components against one another when the retention nut 144 is tightened down on the housing 102. Because there is no isolation of the loading force within the valve cartridge 100, the loading force goes from the seals 104, 108 up to the plates (i.e., the fixed plate 110 and the mobile plate 112) and on through to the actuating mechanism including the carrier 114, the rotatable support member 116 and the operating lever 118. Consequently, the feel of the actuating mechanism by the user is affected by the magnitude of and variations in the loading force. For example, the more force that is applied to the valve cartridge 100, such as by tightening of the retention nut 144, the rougher the actuating mechanism feels during operation by the user.
Because the operating lever 118 is pivoted about the pin 122 relative to the rotatable support member 116 to control the flow rate of the water, and the rotatable support member 116 is itself moved relative to the housing 102 to control the temperature of the water, different frictional forces result from controlling the flow rate and the temperature of the water. Furthermore, because there is no isolation of the frictional forces within the valve cartridge 100, the frictional force between the plates (i.e., the fixed plate 110 and the mobile plate 112), which varies depending on the loading force applied by the retention nut 144, is transmitted up to the actuating mechanism such that the user may experience an inconsistent, imprecise and/or rough feel during operation of the valve cartridge 100.
Accordingly, there is a need in the art for a valve cartridge wherein the loading force on the actuating mechanism is isolated from the loading force applied to the valve cartridge.
Furthermore, there is a need in the art for a valve cartridge having a consistent actuating frictional force that is isolated from other frictional forces within the valve cartridge.